A software keyboard technique is known in which a keyboard image is displayed on a display device such as an LCD and key codes are input to a program such as an OS according to user operations on the keyboard image.
For example, one technique relating to the software keyboard is available which allows the user of a computer system to design a touch-operated keyboard displayed on a display screen without the need for writing codes. A publication JP-A-5-108232 (counterpart U.S. publication is: U.S. Pat. No. 5,936,614) discloses a touch-operated keyboard defining method in which a keyboard editor produces a keyboard display space and the user forms a keyboard image in this display space and determines computer system actions to be carried out when respective keys are touched.
Where the display area of a display device is small, a keyboard image displayed on the display device is also small and it may be difficult for the user to make an operation. One countermeasure would be that a keyboard image in which images of low-use-frequency keys are not displayed is formed using, for example, the technique described in JP-A-5-108232, and images of high-use-frequency keys are displayed in an enlarged manner on a display device. However, the user operability may be lowered in that it may be difficult for a user to use the non-displayed keys.